The present invention relates to a formulation of a fat and a solid surface active agent for use as a carrier for an aroma chemical or fragrance for the purpose of imparting a fragrance to a laundry detergent composition containing the fat/surface active agent formulation used to increase substantivity of fragrances on fabrics. In another aspect, the present invention relates to a method of formulating a fat and surface active agent carrier for one or more aroma chemicals.
The method of the present invention enables the production of fragrances containing solid particles of improved substantivity for use in a variety of laundry detergents.
It has been the practice in the past to impart fragrance to standard powdered laundry detergent by simply spraying the fragrance or aroma chemical onto the detergent base formulation. In such prior art developments, it is typical that the detergent contains at least 0.5% by weight of the fragrance formulation. In the course of the washing process wherein clothes are washed with the standard powdered laundry detergent, a very small fraction of the fragrance that is contained in the detergent is actually transferred to the clothes. Tests have shown that the amount of fragrance that is left as a residue on the clothes can be as low as 1% of the original small amount of fragrance that is contained in the detergent formulations itself. Hence, it will be seen that 1% of as little as 0.5% by weight fragrance is a very small amount of fragrance indeed.
One approach to solve this problem that has been used in the prior art is to employ a carrier to bring the fragrance to the clothes. The carrier is formulated to contain fragrance and to attach itself to the clothes during the washing cycle through particle entrainment or chemical charge.
The procedures of the prior art and formulations of the prior art have not been altogether successful because of the low substantivity of the fragrances. In the detergent industry the term "substantivity" refers to the deposition of the fragrance on the clothes and the retention and perception of the fragrance on the laundered clothing.